Effect of additives on enhanced in-vitro shoot multiplication and their functional group identification of Chlorophytum borivilianum Sant. Et Fernand

An assessment for in vitro propagation and genetic stability of Phoebe goalparensis Hutchinson, an endemic valuable timber tree of North East India

BACKGROUND

Phoebe goalparensis is an endemic forest species of North East India that belongs to Lauraceae family. P. goalparensis is used as timbers yielding plants for commercial importance in the local furniture markets of North East India. A rapid in vitro micropropagation protocol was established by using apical and axillary shoot tips on Murashige and Skoog medium with varied concentrations of plant growth regulators.

RESULTS

In this study, 5.0 mg/l BAP augmented medium was chosen as the best for shoot multiplication of the plant. However, IBA (2.0 mg/l) was the most responsive for root induction. Moreover, 70% of root induction was recorded during rooting experiment and 80-85% survivability was observed during the acclimatization of this species. Clonal fidelity of P. goalparensis was determined with ISSR marker and it was observed that in vitro raised plantlets were polymonomorphic.

CONCLUSION

Hence, an efficient protocol with high proliferation and rooting was established for P. Goalparensis that could aid in massive propagation in future.

Tissue Culture in Ornamentals: Cultivation Factors, Propagation Techniques, and Its Application

Ornamentals come in a variety of shapes, sizes, and colors to suit a wide range of climates, landscapes, and gardening needs. Compared to demand, a shortage of plant materials and diversity force the search for solutions for their constant acquisition and improvement to increase their commercial value, respectively. In vitro cultures are a suitable solution to meet expectations using callus culture, somatic embryogenesis, protoplast culture, and the organogenesis of protocorm-like bodies; many of these techniques are commercially practiced. Factors such as culture media, explants, carbohydrates, plant growth regulators, and light are associated with the success of in vitro propagation. Techniques, especially embryo rescue and somatic hybridization, are widely used to improve ornamentals. The development of synthetic seed allows season-independent seed production and preservation in the long term. Despite the advantages of propagation and the improvement of ornamentals, many barriers still need to be resolved. In contrast to propagation and crop developmental studies, there is also a high scope for molecular studies, especially epigenetic changes caused by plant tissue culture of ornamentals. In this review, we have accumulated and discussed an overall update on cultivation factors, propagation techniques in ornamental plant tissue culture, in vitro plant improvement techniques, and future perspectives.

Incorporation of Organic Growth Additives to Enhance In Vitro Tissue Culture for Producing Genetically Stable Plants

The growing demand for native planting material in ecological restoration and rehabilitation for agro-silvo-pastoral ecosystems has resulted in a major global industry in their sourcing, multiplication, and sale. Plant tissue culture is used for producing high-quality, disease-free, and true-to-type plants at a fast rate. Micropropagation can help to meet the increasing demand for planting material and afforestation programs. However, in vitro plant propagation is an expensive technique compared to conventional methods using suckers, seeds, and cuttings. Therefore, adopting measures to lower production costs without compromising plant quality is essential. This can be achieved by improving the culture media composition. Incorporating organic growth additives can stimulate tissue growth and increase the number of shoots, leaves, and roots in culture media. Organic growth supplementation speeds up the formation and development of cultures and yields vigorous plants. Plant regeneration from meristems (shoot tips and axillary buds) is a reliable way to produce true-to-type plants compared with callus and somatic embryogenesis regeneration, but in vitro culture environments can be mutagenic. Therefore, detecting somaclonal variations at an early stage of development is considered crucial in propagating plants. The genetic stability of in vitro regenerated plants needs to be ascertained by using DNA-based molecular markers. This review aims to provide up-to-date research progress on incorporating organic growth additives to enhance in vitro tissue culture protocols and to emphasize the importance of using PCR-based molecular markers such as RAPD, ISSR, SSR, and SCoT. The review was assessed based on the peer-reviewed works published in scientific databases including Science Direct, Scopus, Springer, JSTOR, onlinelibrary, and Google Scholar.

Micropropagation of Citronella mucronata D. Don, a Vulnerable Chilean Endemic Tree Species

Citronella mucronata (C. mucronata), a tree species endemic to Chile, has become threatened in its natural habitat and is currently listed as vulnerable. Tree population parameters have deteriorated due to indiscriminate logging and other anthropogenic activities, warranting research on mass propagation as a means of recovery. This study, unprecedented for this native species, has developed a successful method for its micropropagation. The objective was to establish a protocol for in vitro propagation of C. mucronata to produce large quantities of high-quality seedlings in an accelerated plant acquisition process. The best results were achieved by growing explants on Murashige and Skoog (MS) basal culture medium supplemented with 4.44 μM 6-benzylaminopurine (BAP) and 14.76 μM indole-3-butyric acid (IBA). Explant survival rate was 78 %, the average shoot length reached 3.2 cm, the number of lateral shoots was 3.9, and rooting rate was 60%. Furthermore, stimulation with red and blue light in a 1:2 ratio, supplemented with 14.76 μM IBA, improved the rooting rate to 93%. The survival rate of rooted explants reached 100% in the acclimatization stage when using peat and perlite substrate (1:1 v/v).

Rapid plant regeneration in industrially important Curcuma zedoaria revealing genetic and biochemical fidelity of the regenerants

The present investigation was carried out to establish an efficient and reproducible micropropagation protocol for the production of morphologically, genetically and chemically uniform plants of Curcuma zedoaria. Axillary bud explants of C. zedoaria were inoculated into MS basal medium supplemented with various combinations and concentrations of 6-benzyladenine (2.2-22.2 µM, BA), kinetin (2.3-23.2 µM, Kin), indole-3-acetic acid (2.9-11.4 µM, IAA), α-naphthalene acetic acid (2.7-10.2 µM, NAA) and adenine sulphate (33.9-203.6 µM, Ads). Almost 95% of rhizome buds sprouted on MS medium supplemented with 13.3 μM BA, 5.7 μM IAA and 63.9 μM Ads giving rise to an average of 12.89 ± 0.02 shoots within 6 weeks. However, the maximum number of roots (25.8 ± 0.07 roots per explant) was obtained on half strength MS medium supplemented with 7.4 µM of IBA after 4 weeks of inoculation. Morphological characteristics were similar in both conventionally propagated and micropropagated plants. Additionally, genetic homogeneity of in vitro plants was further confirmed through ISSR and flow cytometry analysis. A total of 27 ISSR primers were screened, out of which 13 ISSR primers generated 58 monomorphic and reproducible bands thereby confirming the genetic uniformity of obtained plants. The mean 2C DNA content of the mother plant (2.96 pg) was similar to that of in vitro derived plants (3.07 pg). Gas chromatography-mass spectrometry (GC-MS) analysis showed similarity in the qualitative profile of chemical constituents of essential oil and high-performance liquid chromatography analysis revealed no significant differences in curcumin content in the tissue culture regenerants and mother plants of C. zedoaria. Therefore, the present micropropagation protocol could be effectively employed to generate true to type plantlets of C. zedoaria.